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YO5PBG Wavelenght

Amateur Radio, QRP, Home Made

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I just “downloaded” this pictures from YO5PCP’s phone, my friend Zsolt.

First picture shows not only the antenna but also the big differences between human beeings :-). The other human beeing is Geo – YO5PWR.

Here I am, making love with my 2.5m aluminium antenna, mounted on a 1,6m high photo tripod.

At this moment I have the beacon running with the folowing features:

Mode: A1A (CW)

Frequency: 50.067 50.070 MHz

Power output: ~ 1.5 W

Antenna: vertical l/2 dipole (mounted at fourth floor)

QTH: Baia Mare City (Maramures county), KN17SP

Message: VVV de YO5PBG/B KN17SP – - – - – - – - (continous loop)

Keying Speed: ~ 18 wpm

So, once again, like always, i’m very busy.

An old friend of mine, that i met after about 5 years gave me a nice microcontroller, ATtiny2313, a 20 pin IC. He told me something about this unknown “black microboxes”. And convinced me. I was always afraid of them. Of microcontrollers. Instead of using ONE IC for the job I user more than 10 standard CMOS IC’s. At a bigger expense. Of course. Of course, I’m sometimes an idiot, not willig to go one step further for my good.

So thanks to my friend Eduard (Edy, non-ham) i already made my first two ATMEL MCU based projects based on ATTiny2313, in about 2 weeks. Almost simple: one IC, and other 3 components on the board to obtain – in my case – a beacon identifier or a nice frequency meter for testing my homebrew projects.

Otherwise, I’m once again frustrated of big boxes. I decided to move my All Mode – All Band  HF-VHF-UHF transceiver project really started about a year ago to a new, much more sexy, alluminium case. Three times smaller :-). What’s the problem? Doc’, i want to use this transceiver also for portable, when i travel with my bicycle some kilometres away from Baia Mare city, my QTH.

Last week I receiver a stiker from PA amateur radio association for participanting in PACC 2010 contest. Nice! Next year I want to be first in QRP section :-P.
I made big jump over the last 3-4 months in order to improve my shack: I’ve modified transverters, PA’s, etc.
I hardly used my imperfect brain to improve my all-mode-all-band transceiver for HF/VHF/UHF.
I used my new bicycle to improve my spectacular-sexy feets.
I used my mouth to drink enough beer and to smoke lot of tabacooooh to be an honorable “no money man”.

Last week I made a new “big step” in terms of QRO-zing my QRP based shack. This time I moved from the 4-5 watts from my 144MHz transverter to better than 25Watts RF output by making a little (iPhone like dimmensions) 2 meters amplifier. I had an old SRFH 1057 Motorola transistor used in some Philips radiotelephones back in the ’90s.

Otherwise, I’ve also transformed my 2m transverter in terms of appearance. It was housed in an 200x50x100 mm box, now it is housed in an fully alluminium box 3 times smaller and sexy like Me, of course.

The last OTHERWISE is that i heard first stations on 70MHz band. TX is not 100% prepared right now. Stations are:

06/01/2010   16.19   SV5FOUR/B 559 KM46

06/07/2010   12.05   OZ6ZW 57  CALLING (I think it was OZ3ZW, but noted wrong in my log :-) )

06/07/2010   12.10   OZ7IGY   55   BEACON JO55WM

Also heard GB0BUX (hope this is the callsign) BEACON but did not logged this one. Was very “quiet”, down to 519 in my ears.

I have a lot of noise from unknown sources on 70MHz band, so it is very difficult for me to hear much.

Last year I made a litlle experimental transverter from 50 to 70 MHz, but heard no station. I had also limited time to listen the band.

This year the new magic band is also ours. We (romanian amateurs) are able since now to operate 4m (70MHz) band with some kind of special aproval.

I already destroyde last year experimental transverter (HI!) – and I forgot this. So I’m taking it from ZERO.

Today I made another experimental TSVR, but only the receive converter this time, based on: FET oscillator on 20MHz, double balanced mixer, and a little amplifier with bipolar transistor BFX89. A very very simple aproach. It was too late when I finished it (it seems that is working – it “feels” the antenna). Hope tomorrow propagation will help.

Otherwise, I heard loud today ST2AR (Sudan) on 6m, but I don’t know if I did work him, because I have a lot of QRN (static on my vertical), and I’m not quite sure that it was really my callsign that I heard back from him :(. No problem, I have a new girl exciting my senses… 70MHz!

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I bought yesterday an old Zetagi 70W CB PA for 27MHz,  not working or, I believe that it was more about the standard CB operator… that does not know much about what is he using.  I received the PA to repair it, then I told him, that is not suitable for use as PA, neing unstable with CB transceivers exceding 3,5Watts optput. So I bought it from him for the enourmous sum of 50 lei – that means about 12 euro.

I changed almost every component and improved the circuit for class AB operation, and i’ve inserted some new circuit that works well for giving a visual information about the output power. The MRF450A power transistor is working up to 30MHz if you look at the Motorola Datasheet. Really? It gave me better than 10dB gain at 50MHz, althought it is a 13dB gain RF transistor for 27MHz.

This new, improved, YO5PBG :-) 6m all mode PA, gives about 28W (53V/50 ohm) output power for 2,25W (15V/50 ohm) from the transceiver at 12,7V supply. Should be better than 30W at 13,5~13,8V. On the Internet I found another 50MHz MRF450 PA based on old CB amplifier, located here (en francais).

Here is the schematic (click the image to enlarge).

MRF450 50MHz, 6m, PA

I wanted to give it a try becase of the booming signals in 20 meters received Saturday  on my little “balcony” vertical antenna (2,75 m :-)).  I was able to work better USA  stations than Russian stations from the European side HI!  Mostly CW, but also some nice SSB contacts, almost all on 14MHz. I worked only for about 8-10 hours, total time. Only a very few stations heard (also worked), today, on 21MHz.  Nothing on 10 meters.


  • 14MHz CW: 81 QSO, 185 Pts., 18 Cty.
  • 14MHz USB: 24 QSO, 49 Pts., 4Cty.
  • 21MHz: 5 QSO, 10 Pts., 2 Cty.
  • Total: 110 QSO, 244 Pts., 24 Cty
  • Score: 5.856

Here are just 2 pictures of bad quality (excuse my old superslim Panasonic camera) from my hamshack as of May 2010. It is jus a part of what it shoud be… And a lot of lack of space :-).

Most of the equipement is home made.

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I’m very glad to announce that romanian amateur radio stations are licenced since now to work on the 70.000 – 70.300 MHz band. Looks like YO stations interested must ask for permission to use this new band to the Romanian Ministry of Defense.

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